In recent 80 years,light olefins,especially ethylene and propylene,have primarily been produced through steam cracking of petroleum hydrocarbons.Compared with steam cracking,catalytic cracking introduces a catalyst into the process,which makes its operating conditions mild and improves the yield of high value-added products.It is expected that catalytic cracking will become the primary process for olefin production technology in the future.This paper provides a summary of the advantages and disadvantages of common low-carbon olefin production processes both domestically and internationally,as well as their current application status.It outlines the primary reaction mechanisms involved in catalytic cracking,including the free radical mechanism and the carbon positive ion mechanism.Additionally,it discusses the use of metal oxide and zeolite molecular sieve catalysts.The text focuses on analysing the effects of alkali and alkaline earth metals,transition metals,and rare earth elements modification on the properties of ZSM-5 zeolite molecular sieves.The resulting catalysts were analysed for their performance characteristics in improving the selectivity of low carbon olefins.The main research directions for the development of the catalytic cracking process include the development of large-scale industrialized devices,the continuous expansion of feedstock range,and the research and development of high-quality catalysts.These directions will provide an important reference for the industrialized production of low-carbon olefins.
维普
万方数据